William Butler Yeats's poem "The Second Coming" can be quite confusing for readers who don't understand the poet's personal religious and philosophical leanings. Many readers familiar with Christian teachings equate the "second coming" of the poem with the second coming of Jesus Christ, when, according to Christian belief, he will return to earth from heaven to claim his followers. However, this was not the only idea Yeats was attempting to depict in this poem.
Like other English poets before him, including William Blake and Thomas Hardy, Yeats created a personal mythology that went beyond traditional religious teachings. His wife, Georgie Hyde Lees, whom he married in 1917, was his partner in developing his mythology. She practiced automatic writing and received messages that Yeats believed were dictated by spirits. Gyres, winding stairs, and spirals became important symbols that Yeats used to help explain the progress of history and the paradoxes of existence.
The gyre specifically figured into Yeats's understanding of historical epochs. He proposed that history consists of two-thousand-year cycles that can be represented as a gyre: a spiraling motion in the shape of a cone. As one gyre widened toward its culmination, it would spawn a new two-thousand-year spiral out of a violent countermotion. Yeats explained, "The end of an age, which always receives the revelation of the character of the next age, is represented by the coming of one gyre to its place of greatest expansion and of the other to that of its greatest contraction."
With this in mind, it becomes much easier to interpret "The Second Coming." The twentieth century was the end of a two-thousand-year period, "the widening gyre." As such, it took on the character of the epoch to come. Yeats envisioned the coming two-thousand-year period as a sphinx-like creature with "a gaze blank and pitiless as the sun." That creature now "slouches toward Bethlehem to be born." In this poem, Yeats implies that the horrors of the early twentieth century, namely World War I, foretold an unimaginably dire epoch that would come with the dawn of the twenty-first century.